Various schemes exist for organizing photographs or other images. Early versions of on-line or desktop software for organizing photographs followed the paradigm of a physical photo album. In an album, photos are collected together, and are organized by subject or chronology. Other software-based models for organizing photos also have been created. For example, certain web sites allow users to tag the photo with the geographic location at which the photo was taken. Thus, a user who takes a photo while in vacation on Seattle may post the photo on a web site and may apply the tag “Seattle” to the photo, or may apply an even more fine-grained tag such as “Pike's Place Market” (a specific location in Seattle). These tags are often used to facilitate a search—e.g., a user might issue a query for photos of Seattle, and a search engine could find the photo based on its tag.
While organization of photos has become more sophisticated in recent years, an issue that remains is that these schemes focus on organizing specific images, rather than on editing and reasoning with the space that the images represent. In some contexts, working with individual photos—as opposed to underlying objects depicted in the photos—can be cumbersome. For example, suppose that a person is remodeling his home and, to help with the remodeling efforts, takes several pictures of his home as it presently exists—e.g., three pictures of the kitchen, five pictures of the living room, four pictures of the bedroom, etc. The user might put these pictures in an on-line photo album and might make notes on some of the pictures. For example, on one of the pictures of the kitchen, the user might write “We could use a new sink.” However, a problem that arises is that the user's note will typically be associated with the specific picture on which the note was made. If the user is looking at one of the other kitchen pictures, he will not see the note—even though the note applies to the kitchen generally, and not to one specific image of the kitchen.